If you’re pulling out your hair trying to get file associations to work in Vista, but you can’t get the file association to work no matter how hard you try, you may want to check out this thread. Seems the path in the registry to the executable might be incorrect–which can occur if you’ve moved (during a re-install) a program. Here’s the steps to fix it:
1. Open regedit.exe
2. In the left window pane, expand the tree view to:
ComputerHKEY_CLASSES_ROOTApplications<your application executable name>shellopencommand
<your application name> should be replaced with the name of your application. For me it was xemacs.exe
3. In the right window pane, double click (Default). Where you see the path to your program, you’ll notice that the path is wrong. It will be the old path, where your program USED to be.
4. Open Windows Explorer, and go to where the executable of your program is located. Copy the path in the Windows Explorer address bar
5. Back in regedit, paste over the incorrect path using the path you copied from Windows Explorer. Make sure you only replace the path, and not anything extra that happens to be in the Value data text box. (ie. be careful not to erase any quotation marks, or “%1”, or anything else you see there)
6. Press OK, close regedit, and you should be done!
Not sure if this issue appears in all versions of Vista or if it’s something that’s part of some beta issues. But I see online that others are running into this, so I thought I’d post the answer here.
I found it simpler when you are going to reinstal a program to just go to the HKEY_Classes_RootApplications and just delete the entry for that program befoe you reinstall it.